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181.
Avocado (Persea americana Mill.) is a subtropical domesticated fruit tree indigenous to Mesoamerica. It is a member of the Lauraceae family and is separated into three horticultural races (Guatemalan, Mexican, and West Indian) mainly corresponding to their ecological adaptation, botanical, and physiological traits. Main objectives of this study were to characterize the population structure, genetic diversity, and horticultural race of a total of 354 Persea spp. trees whose origin is as follow: 221 trees [P. americana, (218), P. nubigena (2) and P. krugii (1)] from the USDA-ARS-Subtropical Horticultural Research Station, Miami; 105 trees from the Fairchild Farm [P. americana (104) and P. schiedeana (1)], and 28 trees collected in Mexico [P. schiedeana (23) and P. americana (5)]. The complexity of their interracial admixture; as well as mislabeling frequency was also evaluated. Molecular marker analysis utilizing a set of 55 simple sequence repeat (SSR) markers amplified a total of 869 alleles with a mean number of alleles per locus of 15.8 and average polymorphism information content value of 0.71, indicating a high variability in the allele frequency for the collection. Significant deviations from Hardy–Weinberg equilibrium were identified after Bonferroni correction for a large number of loci (48; 87%) due to the presence of null alleles. The main source of variation for this population was found to be within individuals (66.84%), with 19.30% variation among populations, and 13.86% variation among individuals within populations. Moreover, population specific inbreeding indices (F IS ) were calculated for West Indian, Guatemalan, and Mexican [(0.1918; p value 0.0000), (0.1879; p-value 0.0000), (0.0925; p-value 0.0022)], respectively. Bayesian analysis divided the individual genotypes into groups associated with the Guatemalan, Mexican, West Indian races; interracial admixture; complex hybrids and P. schiedeana species. Also, results of the multivariate clustering method (PCA) and genetic distance analyses calculated among all possible individual combinations within the SSR diversity data agreed with Bayesian or Structure analyses results. The 55 SSRs provided complete resolution of all individuals and the estimated mislabeling error was approximately 0.28%.  相似文献   
182.
Wild forest fires are one of the greatest environmental disasters affecting forest resources. Along the coastal zone of the Mediterranean region in Turkey,forested areas are classified as first-degree, fire-sensitive areas. Every year, thousands of hectares of forests have been destroyed in Turkey. In this study, fire-access zones were determined in the Mediterranean forests of Turkey, by utilizing geographic information systems(GIS) technology. The effective reach distance of fire hoses from both sides of roads was considered in order to delineate fireaccess zones. The effective reach distance can vary based on the technical capabilities and hydraulic capacity of fire trucks(minimum and maximum pressures on water pump);terrain structures(uphill, downhill and flat); and ground slope. These factors and their influences were studied in fire sensitive forest areas located in the eastern Mediterranean city of Kahramanmaras? in Turkey. First, terrain structures on both sides of the road network and groundslope classes were determined based on GIS data layers.Then, fire access zones were delineated according to water pressure data, terrain structures, and ground-slope classes.The results indicated that 69.30 % of the forested areas were within the fire-access zones, while the rest of the forest was out of reach the fire hoses. The accessible areas were also calculated for forested areas with different firesensitivity degrees. The accessible areas were 69.59, 69.96,and 67.16 % for the forested areas that are sensitive to fires at the first, second, and third degrees, respectively. This finding has implications for the monitoring and management of fire threats in areas outside of the reach distance.The outside areas should receive extra attention and monitoring during the fire season so that fires are detected ahead of time and management has sufficient time to react.Besides, new roads should be considered for these areas in order to access more lands in a shorter amount of time.  相似文献   
183.
【目的】 采用响应面法对红枣黑斑病的拮抗细菌JK1培养基进行优化,提高其发酵产物中芽孢的浓度。为该菌应用提供数据。【方法】单因素实验确定培养基碳氮源物质,Plackett-Burman试验分析发酵培养基中对JK1发酵影响最重要的主要因素;运用最陡爬坡法对主要因素进行试验,获得主要因素的最适范围。通过响应面分析得到主要因素的最优水平。【结果】优化后的培养基组成为:麦芽浸粉 25.00 g/L、葡萄糖 0.57 g/L、大豆蛋白胨 12.5 g/L、NaCl 2.7 g/L、K2HPO4 0.25 g/L 、MgSO4 0.625 g/L。【结论】在最优发酵培养基培养下,多粘类芽孢杆菌的芽孢数提高了3.4倍,达到4.92×109CFU/mL。  相似文献   
184.
Objective: To report a modified colostomy technique for permanent fecal diversion in calves with colonic atresia. Study Design: Prospective study. Animals: Calves (n=19) with colonic atresia. Methods: Clinical findings, white blood cell counts, radiologic, ultrasonographic, and intraoperative findings were recorded. Calves were randomly divided into 2 groups: group 1 (n=9) had conventional colostomy and group 2 (n=10) had a modified colostomy. Technique efficacy was evaluated by postoperative observation, owner satisfaction, and calf survival. Results: Fifteen (79%) calves were discharged from the hospital; 4 (21%) group 1 calves died within 24 hours after surgery. Two (40%) group 1 calves died 18 and 30 days after surgery and 5 (50%) group 2 calves died 2–60 days after surgery. Eight calves reached slaughter weight (120±10 kg); 5 group 2 calves grew normally but the 3 group 1 calves had lower weight gain. Owners of the calves with conventional colostomy reported that the evacuation of feces was continuous whereas owners of calves with the modified colostomy reported that feces were released through the stoma in intervals. Conclusion: Modification of conventional colostomy by forming an hourglass shaped stoma lessens fecal incontinence but there was no difference in survival rate. Clinical Relevance: Modified colostomy was considered advantageous because of intermittent fecal discharge from the stoma compared with continuous fecal release in conventional colostomy. The modified technique seemingly has a beneficial effect on growth of the calf.  相似文献   
185.
ABSTRACT

Response surface methodology was used to investigate the effect of ultrasound-assisted extraction conditions including solvent:seaweed ratio (10:1–30:1), extraction temperature (30–50°C), and extraction time (30–60 min) on the total phenolic compounds and antioxidant activity of red seaweed (Laurencia obtuse) extracts. The optimum extraction parameters for maximum phenolic content were as follows: solvent:seaweed ratio, 30:1; extraction temperature, 50°C; and extraction time, 42.8 min. The experiment results showed that the solvent:seaweed ratio was the most significant parameter for the extraction. The optimum extraction conditions for maximum antioxidant activity were as follows: solvent:seaweed ratio, 24.3:1; extraction temperature, 45.3°C; and extraction time, 58 min. Under the above-mentioned conditions, the experimental total phenolic content and antioxidant activity value were 26.23 ± 0.75 mg GAE/g seaweed and 120.89 ± 0.81 TEAC, respectively, of seaweed tested, which are well compatible with the predicted contents.  相似文献   
186.
The present study was conducted to study the susceptibility of two different types of Sudanese goats namely: Black Nubian, the Nilotic dwarf goats and ewes of Garag type to experimental infection with Trypanosoma vivax stock isolated from cattle outside tsetse area. The infection caused parasitaemia, anaemia and pyrexia in the infected goats. However, the Nilotic dwarf goats were more tolerant to the infection than the Nubian goats, showing significantly higher values of packed cell volume, haemoglobin concentration, total red and white blood cells counts and significantly low parasitaemia and low body temperature. Garag ewes which were found to be susceptible to T. vivax infection showed different signs of anaemia and pyrexia; it is recommended that comparative studies on sensitivity of this type and other different Sudanese types of sheep to Trypanosomosis should be conducted.  相似文献   
187.
In this study, it was aimed to perform an energy analysis of organic grape production in Besni district of Ad?yaman province of Turkey. In order to determine the energy input-output of organic grape production, the observations and surveys were performed in the 82 organic grape growers in Ad?yaman province. 82 farms were selected on full count method. The data obtained from study were collected from 82 different farms (398.32 hectares) by face to face questionnaires and observations. In organic grape farms, energy input-output analysis was also determinated by observation and survey methods in production season in 2015. In organic grape production, energy input was calculated as 24,875.06?MJ?ha?1 and energy output was calculated as 163,430?MJ?ha?1. Energy use efficiency, energy productivity, specific energy and net energy in organic grape production were calculated as 6.57; 0.56?kg?MJ?1, 1.79?MJ?kg?1 and 138,554.94?MJ?ha?1, respectively.  相似文献   
188.
The goal of this study is to do the energy input-output analysis of organic mulberry. This study was conducted at the organic mulberry producing facilities during the 2015–2016 production seasons in Adiyaman-Tut region of Turkey. The agricultural input energies and output energies used in organic mulberry production were computed to determine the energy input-output analysis. According to the research findings, the energy inputs in organic mulberry production were computed respectively as 3948?MJ ha?1 (59.01%) drip and sprinkler irrigation energy, 1092.42?MJ ha?1 (16.33%) gravity irrigation energy, 449.33?MJ ha?1 (6.72%) diesel fuel energy, 416.52?MJ ha?1 (6.23%) farmyard manure energy, 335.14?MJ ha?1 (5.01%) human labour energy, 253.52?MJ ha?1 (3.79%) machinery energy, 93.12?MJ ha?1 (1.39%) transportation energy, 75.78 MJ ha?1 (1.13%) animal labour energy and 26.62?MJ ha?1 (0.40%) organic fertilizer energy. Total input energy was computed as 6690.46?MJ ha?1. Production output organic mulberry yield were calculated as 37,627.84?MJ ha?1. The energy output/input ratio, specific energy, energy productivity and net energy computations were computed respectively as 5.62, 1.51?MJ kg?1, 0.66?kg MJ?1 and 30,937.37?MJ ha?1. The consumed total energy input in organic mulberry production could be classified as 88.20% direct, 11.80% indirect, 88.10% renewable and 11.90% non-renewable.  相似文献   
189.
Use of Fusarium-infected seed for cereal crops results in a reduced plant density due to seedling blight. This is especially a problem in organic agriculture, for which currently no practical seed disinfection methods are available. In the present paper we investigated whether spring wheat cultivars differ in tolerance to seedling blight in vivo, whether the possible differences could be linked to cultivar differences in initial growth rates, and whether differences in weed infestation were related to differences in emergence. Seed six spring wheat cultivars (Melon, Lavett, SW Kungsjett, Epos, Pasteur, Thasos), containing three Fusarium infection levels were obtained and sown in two field experiments in 2006 and 2007 and in an outdoor pot experiment in 2007. Results indicated that the six spring wheat cultivars differed in their tolerance to seedling blight, and consequently in the percentage of emergence of their seeds. The relative levels of tolerance to seedling blight of the six cultivars were robust in the three experiments performed. No clear relationship between initial growth rates and tolerance was found. In our experiments, no early and homogenous weed pressure was present, but in the 2007 field experiment a relationship between initial seedling emergence and weed infestation after anthesis was determined. Based on the presented results we suggest that additional to resistance to Fusarium head blight (FHB), differences in tolerance to seedling blight should also be considered during selection of wheat cultivars for organic agriculture.  相似文献   
190.
This study was conducted near Hyderabad, India during 1991–1994 to quantify the effects of shoot pruning, fertilization, and root barriers around Leucaena leucocephala trees on intercropped sorghum(Sorghum bicolor) or cowpea (Vigna unguiculata) crop production under rainfed conditions. Crop plants grown with pruned trees attained higher dry matter and leaf area index than did those with unpruned trees. Two-year mean grain yields of sorghum with no root barriers were76% and 39% of pure crop yield (1553 kg ha–1)for pruned and unpruned trees, respectively. Corresponding values for cowpea were 49% and 26% of pure crop yield (1075 kgha–1). Sorghum or cowpea intercropped with trees responded to fertilizer application more strongly than did their respective pure crops, suggesting an increased need for fertilizer application in this agrisilviculture system over that currently used for pure crops. Impact of root barriers was small on either crop. Irrespective of root barriers, a high response to tree pruning suggested above ground competition for light dominated tree/crop interactions in this agrisilviculture system. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
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